Chap. II.] INERTION. 83 



Section III. — Inclination of the Axis of Rotation. 

 But it is clear that the eiFects resultinof from the 



o 



inequality between the forces of the upper and under 

 strata cannot possibly be such as to tend in any way 

 to obliterate or even to change the positions of the 

 districts shown in Plate VI. and just described in this 

 chapter ; for those districts are precisely analogous 

 to those which would be formed by a system of upper 

 and under currents if westward pressure were not 

 deflected by obstructions lying in its course. That 

 is to say, they are analogous to the polar and equa- 

 torial zones described m the second part of this 

 chapter and illustrated in Plate V. Those zones 

 result from a necessary overwhelming of the lesser 

 forces of the lower strata by the greater forces of the 

 upper strata, in case of no obstruction occurring to 

 deflect westward pressure from its natural course. 

 And, in fact, since the deflection of that pressure 

 does not change the relation of the forces of the 

 upper and lower strata to each other, therefore the 

 fact of westward pressure being deflected by the 

 obstruction formed by coast-lines will not obviate 

 the necessity of an overwhelming, to a greater or 

 lesser extent, of the lesser forces of the lower strata 

 by the greater forces of the upper strata ; and there 

 must therefore be formed, notwithstanding the de- 

 flection of westward pressure, in every ocean, a 

 system of upper and under currents analogous to 



D 



